The type of Ink you choose matters to your substrate.
TIJ (Thermal Ink Jet) is an easy to use, convenient method to print MRCs (Machine Readable Codes), human readable text and graphics with superior contrast and crispness, but what ink should you use?
There are two types of ink that are generally used with TIJ. These two inks are either solvent based, usually ethanol and water based or aqueous based inks. Both of the Gx Thermal Inkjet's types of inks have their distinct advantages depending on the type of substrate that you will be printing on. These solvent and water based inks come in a variety of colors, though in most applications, a black ink is used.
Solvent based inks are designed to adhere to substrates such as plastic films (single layer or laminate), blisters, aluminum foils and coated, glossy cartons. These inks provide crisp, clear codes with short dry times allowing fast speeds and eliminating smearing or smudging.
Water based inks are designed to penetrate non-porous substrates such as Kraft corrugate, uncoated cartons or uncoated paper. These inks also provide crisp, clear codes on non-porous substrates, and can still maintain short dry times.
Here at Domino, printing specialists have pioneered water and ethanol-based inks that are fully certified for use in a variety of environments, including food, and are fast-drying and ready for a variety of substrates and applications.
Another consideration when selecting the right ink
While of course dry time and substrate are critical factors to be assessed when choosing the right ink, another one that is often overlooked is related to what is called “decap time” in the manufacturing world.
Decap time is the recommended amount of time that a TIJ ink cartridge can remain uncapped with the printhead exposed to the ambient environment. For the TIJ print head it is important that the nozzles remain wet during the print cycles. Print idle time, also called decap time, should be kept to a minimum to prevent the ink from drying on the faces of the nozzles. Decap time is the maximum allowed time of print idle before the print nozzles no longer remain wet. There are many factors involved in this decap time, but it generally ranges from hours to even days. The general rule of thumb is to replace the cap whenever your production line will be down for an extended period of time, such as overnight or during a long changeover. This decap time can be decreased in production environments with high heat and/or low humidity. The potential time of decap is critical to the integrity of the ink cartridge and the ability to deliver consistent, reliable, accurate codes. The better the decap time, the more flexibility it affords your manufacturing process(es).
So how to get started in making sure you choose the best ink?
Regardless of what ink you think you should use, Domino recommends to always sample a potential ink with the required substrate, and with the worse case (most amount of print) that you would encounter during production. This will ensure that the chosen ink adheres to any given substrate, and you will be able to print any given code within the production speed parameters of your packaging equipment.
Domino offers multiple types of both solvent and water-based inks along with 3 different Tij printers with our Gx-series. Working closely with your TIJ printer supplier will offer depth and understanding in how best to leverage your existing assets to optimize efficiency.
I encourage you to continue the learning experience with TIJ inks with myself via LinkedIn or contacting your local Domino Account Manager.